Machine to Machine (abbreviated as M2M) refers to all technologies and means for establishing connection between machines. M2M concept appeared in the 1990s, but it stayed only in theoretical stage. After the year 2000, with the development of the mobile communication technology, the mobile communications technology makes the networking of the machine equipment possible. M2M service appeared in the market in about 2002 and quickly developed in the following years, it became the focus of attention from various communications equipment companies and telecommunication operators. At present, the number of global machines are much more than that of people, therefore it may be predicted that M2M technology will have good market prospect.
Researches on M2M communication application scenes show that provision of M2M communication on mobile network has potential market prospect. However, M2M service proposes a lot of new requirements on the system. In order to enhance the competitiveness of mobile network in this aspect, it is necessary to optimize the existing mobile network so as to support the M2M communication more effectively.
The existing mobile communications network is designed mainly for communication between people, while communication between machines and communication between people and machine is optimized insufficiently. Besides, how operators provide M2M communication service in low cost is also the key of successful M2M communication deployment.
On the basis of the above conditions, it is necessary to have researches on the solution of how the mobile network supports M2M communication, the solution should reuse the existing network maximally, in order to reduce the impact on the network due to a large amount of M2M communication and reduce the complexity of operation and maintenance.
At present, competition goes increasingly fierce in the telecommunication market. Charge drops continuously, the profit margin declines continuously, and the people-oriented communications market is becoming saturated, so M2M is a new development opportunity for operators.
In order to utilize the mobile network resources effectively, 3rd Generation Partnership Project (abbreviated as 3GPP) proposes Machine Type Communication (abbreviated as MTC), i.e., communication services of Machine to Machine or Machine to Man, the service range goes far beyond the communication between Human to Human (abbreviated as H2H). MTC has great difference with the existing H2H communication mode in aspects such as access control, charging, security, Quality of Service (abbreviated as QoS), service mode or the like.
In 3GPP Evolved Packet System (abbreviated as EPS) architecture, EPS includes radio access network (such as, Universal Terrestrial Radio Access Network (abbreviated as UMTS), Evolved UTRAN (abbreviated as E-UTRAN), GSM/EDGE Radio Access Network (abbreviated as GERAN)) and core network. For example, the Evolved Packet Core (abbreviated as EPC) network includes network elements such as Mobility Management Entity (abbreviated as MME), Serving Gateway, Packet Data Network (abbreviated as PDN) Gateway (abbreviated as PGW) or the like; the GPRS core network includes network elements such as Serving GPRS Support Node (abbreviated as SGSN); and the E-UTRAN includes Evolved Node B (abbreviated as eNB).
MTC Device Trigger is one of basic requirements on the MTC system, the problem on which this requirement focuses is: in order to control communication of the MTC device, communication may be performed in such a manner that an MTC server initiates polling, and for the communication initiated by the MTC device, sometimes it is needed that the MTC server polls data from the MTC device. If the MTC server fails to query or the IP address of the MTC device is unavailable, the MTC server may use MTC device trigger to establish communication with the MTC device. If the network is unable to trigger the MTC device, the network reports MTC device trigger failure to the MTC server and the MTC device trigger is realized in 3GPP via control plane signaling.
MTC device trigger includes Mobile Originated (abbreviated as MO) services and Mobile Terminating (abbreviated as MT) services, that is, it includes that the MTC device sends or receives information.
In order to realize effective transmission of MTC device trigger request, the following solutions have been proposed: sending MTC device trigger information via short message (SMS), or sending MTC device trigger information via control plane signaling. For the mode of sending MTC device trigger information via control plane signaling, the MTC server sends a control plane signaling containing MTC device trigger information to the network node, the network node parses the MTC device trigger information in the control plane signaling and then sends the MTC device trigger information to User Equipment (abbreviated as UE). The MTC architecture in 3GPP is shown in FIG. 1. In the user plane, the MTC application equipment (Application) which connects with the MTC user (User) communicates with the MTC server via an API interface, or directly communicates with the Gateway GPRS Support Node (abbreviated as GGSN)/PGW/Evolved Packet Data Gateway (abbreviated as EPDG) via a Gi/SGi interface; the MTC server communicates with GGSN/PGW/EPDG via an MTCi interface; the GGSN/PGW/EPDG communicates with the User Equipment (abbreviated as UE) via RAN. In the control plane, the MTC server sends a control plane signaling containing MTC device trigger information to the MTC InterWorking Function (abbreviated as MTC-IWF) via an MTCsp interface or sends a control plane signaling containing MTC device trigger information to the Short Message Service-Service Centre (abbreviated as SMS-SC)/IP-Short-Message-Gateway (abbreviated as IP-SM-GW) via an MTCsms interface; the MTC-IWF or the SMS-SC/IP-SM-GW sends the control plane signaling to the MME/SGSN or Gateway MSC for Short Message Service (abbreviated as SMS-GMSC) or short message service router (abbreviated as SMS Router) or Mobile-services Switching Centre(abbreviated as MSC) or Visitor Location Register (abbreviated as VLR), further to send the control plane signaling to the UE via RAN; wherein, the MME/SGSN also can obtain the control plane signaling from a Home Subscriber Server (abbreviated as HSS) or Home Location Register (abbreviated as HLR) (HSS/HLR) via a Gr/S6a/S6d interface.
FIG. 2 is a schematic diagram that the MTC server sends a control plane signaling containing MTC device trigger information via the SMS-SC/IP-SM-GW, wherein the MTC server directly sends a control plane signaling containing MTC device trigger information to the SMS-SC/IP-SM-GW via the MTCsms interface, and then the SMS-SC/IP-SM-GW transmits the MTC device trigger information via the SMS-GMSC, SMS Router, MSC/VLR or SGSN in turn and finally sends it to the UE.
However, at present, in the control plane of the MTC architecture in the 3GPP, as the contents of MTC device trigger information are not determined and there is no solution for processing the MTC device trigger information by the 3GPP network node, requirements on the transmission of MTC device trigger information in the 3GPP network cannot be met.